Contact wheels



Sept. 9, 1958 /J. A. SIMENDINGER CONTACT WHEELS 2 Sheets-Sheet 1 Filed Jun 16, 1955 INVENTOR I J;

' M mwF 7 AT7ro'RNEYs Sept. 9, 1958 --J. 'SIIMENIDINGER 2,850,853

.boNTAcrr'wHEELs 7 Filed June 16, 1955 2 Sheets-Sheet 2 VENT v Jess/w .6): wane ORNEYS BY mmigziii PM 2,850,853 Patented Sept. 9, 1958 tic CONTACT WHEELS Joseph A. Simendinger, Stratford, Conn. v Application June 16, 1955, Serial No. 515,815

2 Claims. (Cl. 51-141) This invention relates to contact or drive wheels especially adapted for backing-up an abrasive belt for abrasive finishing operations.

In the prior art, drums having rubber tire-like faces thereon have been employed as back-up wheels for driving or supporting abrasive belts and the like. Depending upon the belt and object being operated upon, it is desirable to be able to select a wheel surface having the proper Durometer or resiliency for the operation to be performed. Because of this, it has been necessary to have a plurality of complete wheels, :1 complete wheel being relatively expensive, prior arrangements having surfaces not readilychangeable.

One of the objects of the invention is to provide a contact, back-up or drive wheel for abrasive belt finishing arranged so that the desired surface resiliency can be readily. obtained.

Another of the objects of the invention is to provide a contact or drive wheel having an improved manner of anchoring surface inserts.

In one aspect of the invention, the contact or back-up wheel may comprise a metal or solid material drum having its periphery slotted or serrated, the slots extending axially across the periphery of the drum and having widened root portions. In a preferred form, the widened root portion of a slot is circular or circular-like and connects with the narrower slot cut in the drum periphery. Resilient inserts or contact members having face or contact portions extending across the drum periphery can be arranged to be slid into said slots from the side of the drum. The inserts preferably may be made of rubber, which may be extruded. The insert has a root portion matching the widened root portion of the slot, a widened face portion, and a narrow connecting portion joining the root portion and face portion. The narrow connecting portion is arranged to have a tight fit in the narrow portion of the slot and the widened face portion tightly engages the periphery of the drum adjacent said slots. inserts of the desired resiliency or Durorneter can be selected and inserted in the slots in the wheel in accordance with the operation to be performed.

In one manner of using the invention, an endless abrasive belt may pass over the faces of inserts on the drum, the drum or belt being driven so that the peripheral speed of the drum is relatively high. The article to be abraded is then pressed against the belt where it is backed-up by the drum and inserts so that the article is finished as desired. them to give as pressure is exerted against the belt so that there will be a flexing of the belt. This will tend to loosen particles caught therein and will permit the belt, within limits, to conform to the face shape of the article. The separated inserts also will give a cooling effect to the arrangement as the drum revolves and thus will prevent overheating with consequent softening of the rubber.

In a further aspect, the drum may be circumferentially grooved so that the insert material will tend to The gap between adjoining inserts will permit enter the groove and further lock the insert against axial movement. The groove also will tend to further permit the inserts to yield as pressure is exerted against the belt.

These and other objects, advantages and features of the invention will become apparent from the following description and drawings.

In the drawings:

Fig. l is a schematic view of one manner in which the invention can be used; 7

Fig. 2 is an enlarged side view of the back-up wheel of the present invention;

Fig. 3 is a sectional view of Fig. 2 taken along the line 33, the belt and insert being omitted;

Fig. 4 is an enlarged fragmentary perspective view of one form of insert;

. Fig. 5 is an enlarged fragmentary view of a portion of the periphery flange or rim of the drum;

Fig. 6 is an enlarged fragmentary view, showing one manner in which the invention operates;

Fig. 7 is a fragmentary sectional view along the line 77 of Fig. 6;

Fig. 8.is a fragmentary view of a modification of the periphery of the drum of Fig. 3;

Fig. 9 is a sectional view taken along the line 9-9 of Fig. 8 showing an insert in place.

7 The wheelof this invention may be used for various purposes but will be described specifically as a back-up arrangement for an endless abrasive belt finishing or abrading machine. Frame 10 (Fig. 1) may carry wheel 11 and wheel 12, wheel 11 being driven by a suitable motor (not shown).- Endless abrasive belt 13 extends between the wheels, the belt being driven at a relatively high linear speed. Work table 14 provides a support for work piece 15 which can be placed thereon, the work piece being pressed into contact with the abrasive belt 13 so as to finish the face thereof.

In a preferred form, the back-up wheel may include drum 16 (Figs. 2, 3) drum 16 having a hub 17 with an aperture 18 for mounting on a suitable shaft. Annular flange or rim 19 of drum 16 is carried by web 20, annular flange 19 having a plurality of slots 21 extending across periphery 22 of flange 19 or in an axial direction of the drum. The slots have a widened root portion 23, such being circular in the preferred form, it being understood that the widened root portion may take other equivalent forms, not necessarily a true circle.

Inserts 24 (Figs. 2, 4) may, for example, be made from extruded rubber, neoprene or other similar rubberlike or resilient material. Root portion 25 of the insert is connected to'face portion 26 by a narrower connecting portion 27, said portions extending in an axial direction of the drum when in place thereon The underside of margins 28 of face portion 26 are related to root portion 25 and slot dimension so that margins 28 will closely grip the adjoining surfaces of periphery 22 when the inserts are in position on the drum.

As can be seen in Fig. 6, belt 13 is irregularly displaced by workpiece 15 as workpiece 15 is pressed inwardly against the abrasive belt. The inserts directly hereunder will yield to permit the belt to tend to follow irregularities in the face of the work piece. After the belt passes the work piece, the inserts will again resume their original form and tend to flex the belt outwardly so as to eject particles between the abrasive grains.

In the event it becomes desirable to change resiliency of the wheel surface it is merely necessary to slide the inserts from their slots and replace them with inserts having the proper Durometer, diameter, and face width.

The described inserts tend to stay in position when the wheel is being operated and not to slide axially. If required, plates (not shown) could be put on either side of the drum, although such has not been found necessary.

If desired, the wheel may be grooved as seen in Fig. 8, grooves 29 extending at least through the narrow portion of the slot in flange or rim 19, identical parts being given in the same reference characters as in the previous figures, one or more grooves being provided as desired. When an insert is slid into position, such as seen at 39 in Fig. 9, the portions thereof adjacent grooves 29 will tend to press outwardly therein, as at 31, to grip the slot and grooves so as to help hold the insert in its axial position across the periphery of the wheel. As the wheel is rotated, which usually is at a relatively high speed, centrifugal forces will tend to cause the resilient material of the insert to press outwardly into said grooves. Even without the grooves, the widened root portion of the insert under centrifugal force will tend to grip the slot so as to prevent axial displacement of the insert. If a single groove is em ployed adjacent the center of the rim, it will further permit yielding of the insert as the work is pressed against the belt. As mentioned previously, the widened root portion of the insert can be made of various shapes such as circular, square, etc., the root portion of the slot being made in a similar form.

It should be apparent that details of construction can be varied and the construction used for various purposes, such as polishing, without departing from the spirit of the invention except as defined in the appended claims.

What is claimed is:

1. In a contact back-up wheel for an abrasive belt or the like, the combination including a rotatable drum hav- 3 ing a plurality of axially extending slots in its periphery, each of said slots having a widened root portion in said drum, and resilient contact members mounted in said slots, said members having base portions filling said slots and root portions and widened contact portions extending axially of said drum, said contact portions being spaced from each other at their outer face a distance less than their width so that said abrasive belt contacts only the outer face of said contact portions, the space between said contact portions being wider adjacent said drum than adjacent said belt.

2. in a back-up wheel for an abrasive belt or the like, the combination including a rotatable drum having a plurality of axially extending slots in its periphery, each of said slots having a widened root portion in said drum, circumferential grooves intersecting said slots at the surface of said drum, and resilient contact members mounted in said slots, said members having base portions filling said slots and root portions and widened contact portions extending axially of said drum, said contact portions being spaced from each other at their outer faces a distance less than their Widths so that abrasive belt contacts only the outer face of said contact portions, the space between said contact portions being wider adjacent said drums than adjacent to said belt, the base portions of said contact members extending through said slots being extendable into said grooves for anchoring said contact members against axial movement but permitting change of said contact members.

References Cited in the file of this patent UNITED STATES PATENTS 401,215 Ross Apr. 9, 1889 2,581,270 McVey Jan. 1, 1952 2,639,560 Cosmos May 26, 1953 FOREIGN PATENTS 507,718 Belgium Dec. 31, 1951 

